Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1032360AbXEHVXs (ORCPT ); Tue, 8 May 2007 17:23:48 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S967080AbXEHVXo (ORCPT ); Tue, 8 May 2007 17:23:44 -0400 Received: from agminet01.oracle.com ([141.146.126.228]:40298 "EHLO agminet01.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S966321AbXEHVXm (ORCPT ); Tue, 8 May 2007 17:23:42 -0400 Message-ID: <4640EB19.6030005@oracle.com> Date: Tue, 08 May 2007 14:26:49 -0700 From: Randy Dunlap User-Agent: Thunderbird 1.5.0.5 (X11/20060719) MIME-Version: 1.0 To: Jeff Garzik CC: Jeremy Fitzhardinge , Krzysztof Halasa , David Rientjes , Andrew Morton , Paul Sokolovsky , linux-kernel@vger.kernel.org Subject: Re: [RFC/PATCH] doc: volatile considered evil References: <516386418.20070501080839@gmail.com> <20070430235642.e576e917.akpm@linux-foundation.org> <20070508121404.17bd97a6.randy.dunlap@oracle.com> <4640E62D.8060704@goop.org> <4640E8C4.4000603@garzik.org> In-Reply-To: <4640E8C4.4000603@garzik.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Whitelist: TRUE X-Whitelist: TRUE X-Brightmail-Tracker: AAAAAQAAAAI= Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 863 Lines: 24 Jeff Garzik wrote: > Jeremy Fitzhardinge wrote: >> No, David means that "asm volatile (...)" is meaningful and OK to use. I thought it was OK in readl(), writel(), etc... (and in asm), but that's it. (and jiffies) > In a driver? Highly unlikey it is OK. In a filesystem? Even more > unlikely it is OK to use. > > The set of circumstances where 'volatile' is acceptable is very limited. > > You will see it used properly in the definitions of writel(), for > example. But most drivers using 'volatile' are likely bugs. -- ~Randy *** Remember to use Documentation/SubmitChecklist when testing your code *** - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/